Quasi-Landau-level structure in the fractional quantum Hall effect

It is argued that a short-range interaction induces a quasi-Landau-level structure in the filling-factor dependence of the ground-state energy of electrons in the lowest Landau level. The discussion is based on exact numerical results obtained from small-system calculations, and the adiabatic principle of Greiter and Wilczek. It is shown that by attaching a single negative flux quantum to each electron adiabatically, the noninteracting electron ground states occupying higher Landau levels are smoothly transformed into the ground states of a hard-core boson gas in the lowest Landau level. This implies a close correspondence between the noninteracting fermions and the hard-core bosons in the lowest Landau level. Numerical results suggest the possibility of a smooth transition from hard-core bosons to fermions with a short-range interaction, by continuously varying the interaction potential.